N pollution sources and denitrification in waterbodies in Taihu Lake region

Herein presented are the researches of the past few years related to charac teristics of N pollution of waterbodies and N transport from croplands to t he waterbodies in Suzhou and Wuxi regions, the center of the Taihu Lake val ley. Based on the types of waterbodies, concentrations of inorganic N of di fferent forms, concentrations of PO43-, delta (NH4)-N-15 values in river an d lake waterbodies, the pollution sources of N in the river, lake and well waters are distinguished, and comparisons are made of trend of variation an d amplitude of concentration between years, seasons and N pollutants in wat erbodies. The increase in N2O concentration in different waterbodies and hi gh delta (NO3-)-N-15 value in different waterbodies are deemed as an eviden ce of the existence of denitrification in the river, lake and well waters. Moreover, the role of denitrification in the waterbodies plays in stabilizi ng chronically concentration of N as pollutant in the waterbodies and mitig ating N load in the waterbodies.